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Discussion Starter · #1 ·
Hey there. I have been reading through theese forums and have seen sevral mentions of a 500 swap. I saw the pics of the 80 Brougham D'elegance that had it done (BEUTIFUL car by the way) If you missed that thread, Heres a link to the guy's hopepage: http://www.mcsmk8.com/80CAD-500/MAVICA.HTM

Anyhow, I was curious if a similar swap could be done in an 89', and, if so, what kind of modifications would be needed, how to go about doing it, and any tips to an aspiring do-it-yourselfer that might come in handy.:hammer: I know that if I dont end up doing it, some other intrested reader probly will. Hopefully any posts on this thread will help them as well as me!

Thanks in advance,
-Eric
 

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Discussion Starter · #2 ·
Only a few views without posts, so on a related subject...Has anyone ordered an engine from the parts website this forum is linked to? Are they actually a legitimate buisness or just some kinda cheap internet trick?
 

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A 500 will fit in an 89. you may have problems getting through emissions in this state with it though. You need a donor car to pick several parts off of. a 77'8'9 Deville with a 425 oil pan and pickup tube is needed. Radiator, the engine mounts and pulleys. Exhaust manifolds 1st choice RWD 472 or 500 application 2nd choice 425 RWD application. Wiring modification but nothing major. Then you get to the transmission. Either it gets pulled and replaced with a TH400 and you have no overdrive and lousy gas mileage with your current rear alxe ratio so that has to get swapped to a hopefully posi unit in the 2xx:1 range. OR you beef up the current trans. It's much more than a simple swap. The best swap for my money into one of these would be an Olds 403. Largest small block ever made. It can be made to look 100% stock in your car.
 

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I did an Olds 350 swap in my 85 Cutlass. No one could tell it wasn't the original 307. Until I roasted that one rear tire for 400 feet....

On a 350 or 403 swap, get 1981-1984 heads and intake, this will boost compression slightly and give you a factory aluminum intake. Get a 83-85 Olds 442 cam and you will have a great running, in the 210-220 hp range easily, likely more if you don't have a terrible exhaust. And the ECM won't mind one bit. I do not recommend that aftermarket chevy similar grinds like most cam companies make, the 204/214 cam is way too big for the heavy car and will make terrible emissions. It needs 9:1 or higher compression minimum.

The 403 swap is very rewarding. With the stock OD will do well on mileage too, likely little or no loss over the 307 if driven nicely.
 

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1995 ETC, 75 Deville, Cad500 powered 73 Apollo, 94 Mark VIII
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Exhaust manifolds aren't really an issue with either engine, they should come on the donor engine and if not they're real easy to find. The thing with a 403 swap is it has similar issues with the trans/rear. It's less likely to break behind a 403 since a 403 doesn't push the torque a 500 does, but hell if our only aim is to not break things we may as well stay stock.
 

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Discussion Starter · #7 ·
Thanks for the tips. Its obviously a huge undertaking doing any kind of major motor swap. Im not so much afraid of doing all the mechanics as much as I am of finding the parts and getting a decent price in the meantime.Im still a little unsure exactly what Ill end up doing, but information now so I know later is a great thing.
Although the project is going to be on hold for quite some time (Probly start in the spring) Ill start looking for the parts needed to do so now. Im guessing that the parts for the 403 swap would be a little easier to come across (And probly cheaper at that)
What (if any) kind of emissions systems work with theese motors? Is it possible to continue using the smog pump set up from the 307 or will that stuff also need to be pulled from a donor car?
Thanks for the information and keep posting if you think of anything else. your help is much appreciated.

-Eric​
 

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davesdeville said:
Exhaust manifolds aren't really an issue with either engine, they should come on the donor engine and if not they're real easy to find.
Eldorado manifolds will not work. If your donor engine comes from an Eldo and your manifold bolts are frozen then you are looking at a lot of work. Hardly not really an issue.
 

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Discussion Starter · #11 ·
Alot of good information on that site. I think for now Im just going to make the 307 run a bit better, do the body work, and save any kind of engine swaps for later down the road. Ill keep collecting any information on the 307 as well as potential swaps so Im not left scratching my head when the day comes.:hmm:

-Thanks
 

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The Ape Man said:
Eldorado manifolds will not work. If your donor engine comes from an Eldo and your manifold bolts are frozen then you are looking at a lot of work. Hardly not really an issue.
They would probably work with a bit of cutting and welding. Since you'd have to bust out the welder to make the dual exhaust anyway. Besides, about 2/3 of all 500s made were put in RWD applications.
 
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